(1) Field of the Invention
The present invention relates to a portable power generator for charging a compact portable device including a chargeable power supply such as a mobile phone, a personal digital assistant, a shaver, or a portable audio device.
(2) Description of Related Art
In recent years, compact portable devices such as mobile phones or personal digital assistants have become more sophisticated and required a larger amount of electric power. This causes a battery (a secondary battery) used in the compact portable devices to be rapidly exhausted, and the battery needs to be charged at home and also away from home or in transit.
To charge a secondary battery away from home or in transit, portable power supplies that can be quickly charged using a dry cell are commercially available, but the dry cell is disposable to cause a waste of resources and increase costs. A portable power supply using a solar panel has been also proposed, but tends to be affected by the weather.
On the other hand, in recent years, a power generator (a fuel cell) using fuel such as methanol has been noted. The fuel cell can be repeatedly used by adding fuel, and is not affected by the weather.
Such a fuel cell used in a battery charger of a mobile phone has been proposed. See JP-A-2004-158421, JP-A-2004-194434, and JP-A-2004-336995.
The conventional examples using the fuel cell include a flat fuel tank and a flat power supply portion arranged in the front and back, and the mobile phone is removably mounted to the front thereof. In the conventional examples, however, ensuring a sufficient capacity of the fuel tank increases the entire thickness of the charger to prevent a size reduction. Also, the examples do not disclose addition of fuel that is important in usability.
Thus, an object of the present invention is to provide a portable power generator that can ensure the capacity for fuel and can easily add the fuel.
A treatment method of moisture produced during power generation is a problem specific to fuel cells. Moisture produced during power generation has been generally released into the atmosphere as vapor.
In the conventional fuel cell, however, a vent for releasing moisture as vapor is insufficiently formed to prevent an increase in exhaust efficiency. A sufficiently formed vent increases the exhaust efficiency, but also increases the size of the fuel cell itself, which causes the power generator to be less portable.
Thus, another object of the present invention is to provide a portable power generator that can ensure sufficient ventilation and power generation areas in use (during power generation), and becomes compact when carried.